Birds’ nests, beehives and balloons: new tech tackles old ha...

Sydney Trains’ maintenance staff are used to dealing with unusual hazards.

Crew members talk of relocating cockatoos who have nested in poles or having to get permission for a beekeeper to enter the track after an infestation (he kept the swarm).

One engineer speaks proudly of saving a dog that got lost in the rail corridor. Recently, another crew rescued a flying fox pup that became entangled in an overhead wire.

Foil children’s birthday balloons often also get stuck and a section of track in Burwood has become infamous for freshly hung laundry blown from high-rise balconies on to the lines.

But their methods of identifying overhead wires at risk of failure came under unexpected scrutiny earlier this year after a high-voltage wire snapped and came down on a passenger train between Homebush and Strathfield, trapping 300 people and bringing the city to a standstill.

A “sobering” review of the incident led by Dr Kerry Schott revealed that wires had been inspected using binoculars.

The wires, which are made from different copper alloys, oxidise to a green or black colour but, where they have become thin, they return to a shiny, copper colour. On a clear day, you can see the thin spots.

“While looking at wires through binoculars does on the face of it sound weird, the difficulty with it is that we do need to keep the trains running,” Schott said.

In 2020 the wire in question had been identified as too thin for operational use, below a “condemning limit” of 10.9mm. No action was taken, although it was inspected with binoculars as recently as April.

Five times faster

Now a French-designed laser system is being introduced in the hope of improving the speed and efficiency of maintenance checks on the wires.

At an exclusive demonstration at a siding in western Sydney, Dale Curran, a senior maintenance director for Sydney Trains, shows the “forking-in” points: where the overhead wiring of one track meets the wiring of the next.

This section of track, where the laser system is being demonstrated, is used only by freight trains, but the Homebush incident happened at a point not far away where multiple passenger lines converge.

When Schott’s report was released, the New South Wales transport minister, John Graham, said a network-wide digital scan had identified 126 additional “points of interest” on the network, which had since been resolved.

As we gaze at the track, Curran says additional inspections of every forking-in point on passenger lines have been completed as of “20 minutes ago”.

The new system involves a laser on a retractable fibreglass pole, which is pushed along a section of wire, giving an accurate digital reading with every step.

It may not look like much – and the technique takes some getting used to, as Curran discovers – but the crew says it allows them to measure sections of wire five times faster than previous “single-point” inspections.

The new device is the only one in use on the network, but the government has ordered more to replace binocular inspections for overhead wires by December.

Safety is taken very seriously. Before the demonstration, the crew goes through three consecutive safety briefings, and not just for Guardian Australia’s benefit. If they come across an unexpected hazard during their work, the process starts over.

Crews carry out 5,000 inspections every week across 260,000 assets, which can be as long as several kilometres of track.

At any one time, there are typically 45,000 defects across the network, ranging from an imminent risk such as the Strathfield wire to a rusty bolt, which Curran says “might take another 50 years” to have an impact.

“We track everything,” he says, and binoculars will still be used to inspect these smaller defects.

But change is afoot.

The NSW government has committed to all 12 recommendations in Schott’s report. They include a radical overhaul of Sydney Trains’ maintenance systems, with an investment of $458.4m over four years.

It has committed to moving from a time-based maintenance program to a more risk-based one, including the declaration of “maintenance critical zones”, such as the area around Strathfield.

Curran, a trained electrical engineer and 20-year Sydney Trains veteran who has also worked on the London underground, says it can be hard to talk about his job “at a barbecue”, with inevitable questions about rail delays. But he says the network is serious about improvement.

“We’ve got some work to do in areas that are obvious,” he says.